This invention relates to locks and the like, with particular application to a safety lock for a gun and has other applications for controlling the locking and unlocking of a briefcase or drawer, for example.
Various locking devices exist for controlling the operation of various types of mechanisms. One of the most common locking mechanisms is the conventional key lock. A conventional key lock is, however, not practical for controlling the operation of a gun because a two step procedure would be required to operate the gun; first, the key must be turned to deactivate a locking mechanism and secondly the trigger of the gun must be pulled in order to fire a projectile. This, of course, would not be practical in cases where the gun is in the hands of a policeman, as for this application the gun must be ready at all times.
Various locking devices for controlling the operation of a gun have been developed, some of which are described in U.S. Pat. Nos. 4,067,132, 4,135,320 and 4,154,014, all to Smith. Basically, each of these references discloses a weapon locking device employing a magnetic ring worn by a user of the device and a magnetically responsive member inside the weapon which is moved into or out of an interfering relationship with a working part of the weapon by the magnetic influence of the ring worn by the user. A devious user could, however, activate the mechanism simply by lashing a magnet in the vicinity of the magnetically responsive member thereby permanently enabling the gun to be fired.
Other attempts to control the actuation of a gun have been disclosed by U.S. Pat. No. 4,003,152 to Barker et al, U.S. Pat. No. 4,105,885 to Ornstein, U.S. Pat. No. 4,354,189 to Lemmelson, U.S. Pat. No. 4,457,091 to Wallerstein, U.S. Pat. No. 4,467,545 to Shaw Jr., U.S. Pat. No. 4,488,370 to Lemmelson, U.S. Pat. No. 5,016,376 and U.S. Pat. No. 5,123,193 both to Pugh, U.S. Pat. No. 5,062,232 to Eppler and U.S. Pat. No. 5,192,818 to Martin. Each of the devices described in the immediately above patents, however, employs an electrical circuit for actuating a solenoid connected to the firing mechanism of the firearm. Of course, the use of an electrical circuit requires electrical power, usually in the form of a battery and batteries are susceptible to depletion and require replacement from time to time. Thus, maintenance on the firearm is increased.
There exists, therefore, a need for a device for controlling the actuation of an actuator, requiring no electrical power and/or more difficult to defeat than the Smith devices. The present invention addresses such a need.